I just got one here...
me: Hi, I'm just here to collect my wheelset. (Hands docket for truing service)
A few minutes later mech came out with the wheelset.
me: So is everything fixed now? Do you mind if I check it?
mech: Sure. (Hands me the wheelset confidently)
me: I can't really tell (by spinning). Do you mind showing it to me on your truing stand.
Mech (A bit hesitant now): I managed to true the rear wheel back, but I can't really do much with the front wheel because there's a stuck nipple on one of the spokes
So he put the wheels one by one on his truing stand and proceed explaining what he'd done.
me (surprised that it's actually looking worse than before): Wow! The front wheel still looks quite wobbly ...
mech (interrupting quickly): Yeah well as I said there's a stuck nipple on the wheel and there's nothing much I can do about it. I did the best I could with it.
me (still not satisfied): Well is there anyway to fix it at all? I don't mind paying a little bit extra (was implying at nipple replacement cost).
mech: Yeah I can but it might be about 2-3 hours labour and we charge $85 an hour.
To cut the story short, I ended up paying for it as I didn't really want to continue arguing there and walked out feeling very pissed.
FYI, went to another bike shop later on and the bike shop laughed when I told him the story. This bike shop sprayed a little bit of lube to free the frozen nipple on the front wheel and trued it nicely. Great service too.
This was about two days ago. This morning when I took the wheels for a ride I realized that the rear wheel has extreme uneven spoke tensions. I don't have a tension meter ATM, but some of the spokes basically hardly had any tension on them!!!!
And this was a big bike chain store in my area charging premium on everything (wheel truing is $35/wheel)